The U.N.'s World Food Program says months without rain in southern Somalia have led to a serious food shortage that is affecting as many as 500,000 people. The agency says the worst affected areas are Gedo, Bay, and Bakool, prime-growing areas in the southern part of the country.

In normal years, Gedo, Bay and Bakool produce up to 75 percent of Somalia's sorghum crop. This year, the World Food Program says the region is likely to produce little more than 10 percent of the country's sorghum because of the lack of rain.

WFP spokeswoman Christiane Berthiaume says Somalia will need 40,000 tons of food assistance in the coming months to avoid what she calls a humanitarian tragedy. "The dry weather has also affected very seriously the grazing for the livestock," she said. "And many, many families have already begun to take their animals very far away in order to find food for them. Migration is normal in this part of the country, but it is starting too early this year. So it is a sign of what we call pre-famine."

The World Food Program is appealing to donors to respond urgently. Ms. Berthiaume says food must be brought into Somalia soon to prevent more people from leaving their homes and losing what little they have left. "It is very, very poor families that are affected, and they are at the end of their resources," she said. "Most of the poor households have no stocks from previous years, and the possibility of finding jobs or income is very, very limited in that part of the country."

Ms. Berthiaume says the Bay-Bakool sorghum belt is one of the most productive areas of Somalia, and the effects of this year's crop failure could be far reaching. She says food will be less available in markets throughout the country, and this means prices are likely to rise significantly in the coming months.